Pulse wave sensor

Abstract

Among the technical characteristics disclosed in this specification, the pulse wave sensor with one of the technical characteristic includes a construction to detect the pulse wave at a wrist (i.e., a construction to measure the pulse wave to be worn at the wrist). To be more concrete, the pulse wave sensor includes a measurement unit to measure the pulse wave, a power source unit to supply power to the measurement unit, a cable to connect between the measurement unit and the power source unit electrically, and a armlet type housing to contain the measurement unit, the power source unit, and the cable.

What is claimed is: 
     
       1. A pulse wave sensor comprising:
 an armlet construction to be worn on a wrist of a living body and to measure a pulse wave, wherein the armlet construction comprises: 
 a plurality of measurement units to measure the pulse wave, 
 a plurality of power source units to supply power to respective ones of the measurement units, 
 one or more cables to connect electrically between respective ones of the measurement units and a corresponding one of the power source units, 
 a controller to perform ON/OFF control of each of the measurement units, 
 an acceleration sensor portion, and 
 an armlet type housing to contain the measurement units, the power source units and the one or more cables, wherein the measurement units are equally spaced from one another around the armlet type housing, 
 wherein each of the measurement units comprises a light sensor to detect an intensity of light emitted toward the wrist and penetrating a living body, and 
 the number of the power source units is smaller than that of the measurement units, and power is supplied from each power unit to a different respective sub-group of the measurement units, and 
 wherein, based on the output of the acceleration sensor portion, the controller controls some of the light measurement units to be ON, while others of the measurement units are OFF. 
 
     
     
       2. The pulse wave sensor according to  claim 1 , wherein each measurement unit comprises a light emitting portion, and wherein an output wavelength of the light emitting portion belongs to the visible light region and is smaller than or equal to 600 nm approximately. 
     
     
       3. The pulse wave sensor according to  claim 1  further comprising:
 a display unit provided at the armlet type housing to provide display information. 
 
     
     
       4. The pulse wave sensor according to  claim 1  wherein the measurement unit comprises:
 an amplifier circuit to amplify an output signal of the light sensor, and 
 a processing circuit to acquire information related to the pulse wave based on the output signal of the amplifier circuit. 
 
     
     
       5. The pulse wave sensor according to  claim 4  wherein the measurement unit comprises a substrate having a surface on which the light sensor is mounted and having a rear face on which the amplifier circuit and the processing circuit are mounted. 
     
     
       6. The pulse wave sensor according to  claim 1  wherein the power source unit comprises:
 a battery, and 
 a power source circuit to convert an input voltage from the battery to an intended output voltage. 
 
     
     
       7. The pulse wave sensor according to  claim 6 , wherein the power source unit comprises a charge circuit to perform charge control of the battery. 
     
     
       8. The pulse wave sensor according to  claim 7 , wherein the charge circuit receives a power supply from outside by a contact method. 
     
     
       9. The pulse wave sensor according to  claim 7 , wherein the charge circuit receives a power supply from outside by a non-contact method. 
     
     
       10. The pulse wave sensor according to  claim 1  further comprising: a communication unit to transfer the measurement data acquired by the measurement unit to the outside of the pulse wave sensor. 
     
     
       11. The pulse wave sensor according to  claim 10  wherein the communication unit comprises:
 a memory to store the measurement data, and 
 a wireless communication circuit to transmit the measurement data wirelessly to the outside. 
 
     
     
       12. The pulse wave sensor according to  claim 1 , wherein the armlet type housing is a water-proof construction. 
     
     
       13. The pulse wave sensor according to  claim 1 , wherein the armlet type housing is made of an elastic element. 
     
     
       14. A pulse wave sensor comprising:
 multiple light sensor portions to detect an intensity of light emitted to a wrist and penetrating a living body, 
 a controller to perform ON/OFF control of each of the multiple light sensor portions, and 
 an armlet type housing to contain the multiple light sensor portions and the controller, 
 wherein the controller is configured to judge whether or not the frequency of each output peak of the multiple light sensor portions is within a predetermined range, and turn OFF particular ones of the multiple light sensor portions based on a judgment result which indicates that the particular light sensor portions have frequency abnormality. 
 
     
     
       15. A pulse wave sensor comprising:
 multiple light sensor portions to detect an intensity of light emitted to a wrist and penetrating a living body, 
 a controller to perform ON/OFF control of each of the multiple light sensor portions, 
 an armlet type housing to contain the multiple light sensor portions and the controller, and 
 an acceleration sensor portion, 
 wherein, based on the output of the acceleration sensor portion, the controller controls some of the light sensor portions to be ON, while others of the light sensor portions are OFF.